Enables chromatin DNA binding activity. Involved in several processes, including alpha-beta T cell lineage commitment; positive regulation of DNA demethylation; and regulation of positive thymic T cell selection. Acts upstream of or within hematopoietic or lymphoid organ development and positive regulation of natural killer cell differentiation. Located in nucleus. Is expressed in several structures, including alimentary system; genitourinary system; nervous system; sensory organ; and skeleton. Orthologous to human TOX (thymocyte selection associated high mobility group box). [provided by Alliance of Genome Resources, Apr 2022]